An exhaust treatment apparatus is mounted on such a work vehicle as a hydraulic excavator, a bulldozer, and a wheel loader. As the exhaust treatment apparatus, for example, a diesel particulate filter apparatus (DPF), a diesel oxidation catalyst apparatus (DOC), a selective catalytic reduction apparatus (SCR), and the like are available.
In this regard, in an exhaust gas guided to the selective catalytic reduction apparatus (SCR), a reducing agent is injected from a reducing agent injector in advance and mixed.
Since a temperature of the exhaust gas is high, a temperature of the reducing agent injector may also increase. In order to suppress increase in temperature, a coolant is commonly circulated for cooling.
A coolant, however, is supplied by a cooling pump with the use of engine output, and circulation stops as the engine stops. If the engine stops while the reducing agent injector is in a high-temperature state, a cooling function may not effectively be exhibited.
Japanese Patent Laying-Open No. 2012-137037 proposes a scheme for giving notification to prevent an engine from stopping when solidification of a reducing agent is likely because of a possibility of solidification of the reducing agent around an injection valve due to heat and resultant clogging in case of engine stop while a reducing agent injector is in a high-temperature state.